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If you are looking for gardening advice, tips and solutions, use McGregor’s Help Shed for answers to all your gardening questions. The smallest and simplest tricks can make all the difference in your garden. Use the ‘Ask a question’ tool to submit your own questions for our gardening experts.

Latest Questions & Answers

Damage can be sudden and dramatic as swarms move from tree to tree. There’s little that can be done as their arrival is so random, appearing at any time from September until late December. There’s no point spraying in advance.
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Garden soil tends to drain poorly, especially when it’s used in small seed-starting trays. It can also harbor disease organisms that can damage or kill young seedlings. You’ll get the best results by starting seeds in a lightweight mix formulated specially…

Rust is common on roses, broad beans, alliums and ornamentals; it is best to buy resistant varieties. Make sure to dispose of infected leaves, avoid watering foliage and don’t overuse high-nitrogen fertiliser. Spray with Neem Oil in summer or organic Lime…

Citrus scab covers the skin with warty marks. Damage is mainly cosmetic, flavour and juiciness being unaffected. Dispose of fallen leaves from infected fruit (not in compost). Prune trees with an open centre to increase air movement. Spray with copper…

These popular bulbs can be grown in full sun or in partial shade. Plant the daffodil bulbs at a depth equal to three times the height of the bulb. The dwarf varieties should be spaced 10 to 15cm apart and taller varieties 20 to 25cm apart.…

Cut down the numbers by providing the earwigs homes with crumpled newspaper inside upturned post. Burn the newspaper, earwigs and all, use Diatomaceour Earth to keep earwigs away from strawberries by dusting the plans and…

Follow them home at dawn or dusk to locate their nest then, at night when all the wasps are home spray the nest with a household bug spray. Alternatively if you are feeling brave you can cut the stalk of the nest and drop it into a plastic bag, quickly tie…

A white fungal growth on the base of onion bulbs is a sign of the disease called white rot. This fungus affects onions, and leeks, but is less common on chives, garlic and shallots.
The leaves of the onion become yellow, die back…

A white fungal growth on the base of onion bulbs is a sign of the disease called white rot. This fungus affects onions, and leeks, but is less common on chives, garlic and shallots.
The leaves of the onion become yellow, die back…

Strikes when stone fruit are nearly ripe and spreads rapidly. Salvage the crop, cut out the bad bits and cook or freeze. Remove all trace of diseased fruit from the tree. Spray with copper in winter to kill the spores. Repeat copper spray just before bud…

Most seed packets tell you how deep to plant. A rule of thumb is to sow seeds two or three times as deep as they are wide. Take care not to plant seeds to deep. A seed contains a limited supply of stored food to nourish it during germination. If you plant…

Creating a worm farm is a great idea for getting rid of kitchen scraps. Plus it creates a natural
(and low cost) fertiliser and gives the kids a low maintenance project they can own. Worms turn food scraps into a soil amendment called…

Hold a jar under the bugs and they’ll often leap off the plant into the jar. Crush the beetles-but wear gloves! The stinky smell causes other bugs to drop to the ground where they can be stepped on. Grow Sunflowers and Cleomes as a catch crop to attract the…

Many perennial weeds require deep digging to winkle out their roots. It’s all too easy to leave the root fragments behind; dandelions and twitch are notorious for this. A glyphosate based herbicide such as McGregor’s Weed Out is a good choice for twitch…

Garlic is easy to grow in a sunny position and well-drained soil. Prepare your soil well. Mix in lots of good compost before you start planting. Break up the bulbs no longer than 24 hours before you plant them. Place the cloves 3-4cm below the surface,…

Choose a sunny position where the soil is well drained. Dig the area in autumn, incorporating well rotted manure or garden compost. Approximately seven days prior to planting or sowing apply McGregor’s Vege & Ornamental Plant…

Weeds are here to stay, the seeds arrive in your garden in various ways, by sticking to your shoes, clothes, or are carried in by birds and wind. Here are some tips to help keep weeds at a manageable level.
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Tomatoes and other fast-growing plants may outgrow their pots before it’s time to move them into the garden. About a month after sowing or when seedlings are about 4’’ tall, gently remove one of the seedlings from its pot. If the roots are beginning to fill…

Pull out any summer herbs and vegetables that have finished producing and add to your compost bin. Planting of winter seedlings will give you a good start in your home edible patch so prepare the soil. Plant seedlings of cabbage, cauliflowers, broccoli,…

Prior to sowing it is important to remove all weeds. Perennial weeds should be treated with a McGregor’s Weed Out Advanced as this will kill the roots. Once any weeds have died the area can be dug, removing any roots and large stones. Rake over the area to…

Root rot caused by fungi can kill host plants (grapes, trees, apples, and tomatoes, heather). Roots die back and whole branches may collapse. Progress may be slow as trees lose limbs over several years. Cut away infected material. Site new plantings on…

When plants are stressed by high temperatures, they are far more susceptible to attacks by garden pests.
Here are a few common summer garden gremlins to look out for:
Red spider mite breeds at a rapid…

Ladybirds predate mealybugs. Be selective with sprays as many won’t be effective against mites but will harm ladybirds. Ensure the underside of the leaves are thoroughly covered with spray and repeat several times at seven-to 10 day- intervals.
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A black fungus layer that grows on the excretions of sap-sucking insects and can decrease photosynthesis of the leaves. Find and treat the offending insects with Neem or an oil spray. Wash sooty mould off small plants with tepid, soapy water.…

When a tree or shrub is cut down the majority of the plant may be left in the ground as a substantial root system. The stump often re-sprouts with renewed vigour. Even if the stump is removed, some trees and shrubs will re-sprout from small pieces of the roots left in the…

Broadleaf weeds such as Onehunga weed, daisies, hydrocotyle, clover, dandelions and thistles can spoil your lawn. Dig them out with a kitchen fork, knife or screwdriver, making sure you remove every centimetre of root so they don’t simply re-sprout. For…

Clovers are an extremely common weed found in gardens throughout New Zealand. Clovers have creeping stems and distinctive leaves which are quite small and slightly notched at the tip. Clover flower heads are often visited by bees. There are several species…

Hydrocotyle has a hariy leafy which is often stalked at the centre. It is a mat forming weed, making it usually widespread. Use McGregor’s specialised Hydrocotyle lawn weed control for the best results.…

Mold is an indication that the growing medium is too wet. It will not hurt your plants as long as you take action. Withhold water for a few days and try to increase air circulation around the containers by using a small fan. You can also scrape some of the…

The issue you are facing is known as leaf roller caterpillar. Young leaves get stuck together and/or have numerous small holes with a chewed appearance. If the leaves are stuck together the small caterpillar can usually be found between the…

Acid Lawn Soil restricts grasses ability to absorb nutrients, making it appear pale and weedy. Check the pH levels with a soil tester, neutral is between 6.5-7.0, if your pH level is lower add Lime to your lawn as this will raise the pH level and help improve soil…

Plants grow tall and leggy when they do not receive enough light. Use grow lights to ensure that they receive 15 hours of bright light each day. Warm temperatures can also stimulate leggy growth. Try lowering the room temperature and reducing the amount of…

When the stem of young seedlings become withered and topple over, they have probably been killed by a soil-borne fungus called “damping off”. This fungus is difficult to eradicate once it is present in the soil, but you can avoid it by using a sterile,…

There are a number of factors that affect germination. Check the seed packet to determine if all the requirements for temperature and light were met. If the soil was cold and excessively wet, the seeds may have rotted. Dig up one of the seeds and examine…

Purple leaves are an indication that the plant is not receiving enough phosphorus. If you have been using half strength fertilizer for the first three to four weeks of the seedling’s life, it may be time to increase the fertilizer to full strength. The…

This is most likely Onehunga weed or Prickle weed, it is a bunched prickle that can make walking on the lawn painful. Treat Onehunga with McGregor’s Onehunga Weed Out treatment for specialised results.
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They could be Leaf Roller Caterpillars; they tie up the leaves with a web. You need to get rid of them to stop them creating skeleton leaves. Use McGregor’s Derris Dust on your plants, it is safe for edibles.…

Oriental vegetable varieties have becomes a part of our everyday diets. And, like other fresh vegetables, they taste better if they’re grown in the home garden and harvested just as they’re required. Many grow easily from seed, which means you can…

Blue and yellow flowering plants are the best plants for bees. These plants are even better if they are mass planted so bees can spend their time foraging in one area. Our native Hebe is also a bee magnet, as are fruit trees such as apple, pear, citrus and…

No volume of gardening brilliance can overcome the need for a few essential gardening tools:
Sturdy Spade
What’s a garden without a trusty spade? You’ll need a substantial one for digging large holes if you're…

PROS: Raised beds are ideal if you have a sloping site or the soil is heavy clay or very sandy. They look smart and allow for easy crop rotation. They keep the soil a few degrees warmer, enabling an earlier start in spring and later cropping in autumn. If you are new to gardening,…

Blight thrives in warm, humid weather. Leaves turn brown and spread rapidly up the plant, which may collapse. Grow tomatoes inside to keep leaves dry, water at the base. Remove and burn infected leaves and rotate crops. Use copper-based spray such as copper…

Use a hoe on gravel paths or spray with a glyphosate-based herbicide. Be careful of spray drift – spray only on a still day, and hold up pieces of cardboard to protect nearby plants. You can use a knife or weeding tool with a hook to remove weeds from…

Yarrow is a common weed of pastures, roadsides, gardens and waste places. It has feathery branched leaves and sends up a flower stalk topped with a disc of white or pink flowers. It spreads easily by sending out rhizomatous roots from which new plants grow forming a dense mat of…

Hardening off is simply acclimating plants to outdoor conditions. Seedlings grown indoors have been coddled – you’ve been giving them just the right amount of light, moisture and nutrients. Outdoor conditions are more challenging, with fluctuating…

Peaches and nectarines with red, blistered and curled leaves are showing signs of leaf curl, which can debilitate the tree. Pick off the worst leaves. Spray with a fungus control liquid every week or two during spring (except during blossoming) until all…

Control invasive weeds such as 'Wandering Willie' (Tradescantia Fluminensis) and 'Convolvulus' with herbicide. Spray only during warm, dry spells and be prepared to do follow-up sprays. Spray the whole plant, and then follow up with another spray two or…

Aphids cluster at the tips of new growth so a quick, effective control is to squash them with your fingers. Attract beneficial insects that eat aphids. Spraying with Neem oil knocks back the aphids but won’t harm larger beneficial insects.…

There are several species of thistle that are weeds in New Zealand; Nodding Thistle, California Thistle, Scotch Thistle and Sow Thistle. Californian Thistle is a perennial and can be difficult to control due to vegetative growth from its creeping and spreading root system. In mown lawns it…

If you’re new to growing seeds, begin with easy, reliable seeds, including Tomato, Pepper, Basil, Zinnia, Marigold and Cosmos. These all germinate readily and grow quickly. Once you’ve mastered these, you can try your hand at more challenging plants.
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Not all vegetable plants like the same growing conditions, so it’s best to pair the mulch with the crop. For instance, heat-loving peppers, tomatoes, eggplant and melons are great candidates for black plastic mulch. Applied in early spring, the…

It’s still not too late to plant out sweetcorn seedlings, especially if you live in a warmer area. In colder places go for a short-season variety. Choose a position sheltered from strong winds with plenty of sun and well-drained soil. Dig plenty of compost,…

Mineral oils, such as McGregor’s Spraying Oil, seep under their protective coating to smother the bugs underneath. Systemic insecticides (Orthene, Confidor) are taken up by plants and transferred to bugs via the sap. Soak the root ball of mealybug-infected…

For effective control, sprays need to be timed for when the moths are flying. Hang pheromone traps in early spring. Count the number of male moths stuck in the traps every couple of days. When you get a dozen it’s time to spray with a caterpillar spray as…

Clear away the grass to give access to the tunnels. Thread in supple wire to spear the grubs. Don’t prune affected branches in spring or summer- adult borer will lay more eggs on the fresh cuts. Prune in autumn or winter when the adult’s aren’t…

Common nocturnal pests of the home garden with a voracious appetite for young seedlings and a number of ornamental plants such as Hosta, and the native Reinga Lily. They thrive in damp conditions (winter-spring) or where there is cover from daytime sun.
Solution: …

Perennial herbs, such as rosemary, oregano, thyme, chives, bay laurel and mint are easiest to grow from seedlings that you can purchase at a garden center. You can also use small plants dug from your garden. Many herbs can be started from cuttings, too. For…